As adjectives the difference between starch and starchlike
is that starch
is stiff; precise; rigid while starchlike
is resembling starch.
As a noun starch
is (uncountable) a widely diffused vegetable substance found especially in seeds, bulbs, and tubers, and extracted (as from potatoes, corn, rice, etc) as a white, glistening, granular or powdery substance, without taste or smell, and giving a very peculiar creaking sound when rubbed between the fingers it is used as a food, in the production of commercial grape sugar, for stiffening linen in laundries, in making paste, etc.
As a verb starch
is to apply or treat with laundry starch, to create a hard, smooth surface.